The present invention relates to a chassis which houses multiple circuit cards, and in particular, a chassis for industry standard PC 104 circuit cards.
In many electronic applications today, circuits are burned into an integrated circuit chip, which in turn is electrically connected to other integrated circuit chips via their placement on a circuit board. The circuit board can then be installed into a system involving computer control and/or other purposes. Thereafter, if there is any problem with the operation of the circuit card within the system, the circuit card can be easily replaced with a new one.
The ubiquity of circuit cards has led to some standardization of circuit cards. One standard, the PC 104 standard, is used in a variety of environments ranging from personal computers to components of aircraft systems, naval ships and rocket launched vehicles. In some of these environments, such as the aircraft systems or rocket launchers, the circuit cards may be exposed to extreme shock, vibration, and extreme temperatures, all of which can damage the circuit cards. Because of the harsh environment that PC 104 circuit cards may be exposed to, there is a need for a system to protect these circuit cards.
The present invention is a circuit card chassis which receives, holds, and electrically connects circuit cards, and in particular, standard PC 104 circuit cards. The invention is particularly useful for PC 104 circuit cards which are used in harsh environments such as aircraft systems, naval ship and rocket launched vehicles. The chassis consists of a front face, a connector end opposite the front face, and housing walls on its side and bottom. The front face includes features such as a cable restraint handle mechanism, I/O connectors, mounting hardware and installation jacking type screws. The connector end includes alignment pins, I/O connector pins, and an I/O connector pin guard.
The chassis has a top cover consisting of two longitudinal braces and one or more transverse guards attached to the longitudinal braces. The top cover is held in place by fasteners which connect the longitudinal braces to the side walls of the housing.
The chassis holds one or more circuit cards in a stack through the use of spacers, spacer brackets and stabilizer rods. The stabilizer rods penetrate holes in the circuit cards, are attached to the chassis housing, and hold the circuit cards firmly in place. The spacers and spacer brackets maintain a cushion of dead space between the circuit cards. This dead space helps to prevent any damaging contact between circuit cards, and provides a path for forced convection air to pass over and around the circuit cards. The stabilizer rods, spacers, and spacer brackets are made out of stainless steel, which impart strength and sturdiness to the chassis and circuit card stack thereby protecting the circuit cards.
These aforementioned features of the invention, along with other features of the invention, satisfy the following objectives.
It is an object of the present invention to maintain the operation of PC 104 circuit cards in harsh environments.
It is another object of the present invention to maintain the operation of PC 104 circuit cards in environments that include shock trauma.
It is a further object of the present invention to maintain the operation of PC 104 circuit cards in environments that include shock trauma.
It is a still further object of the present invention to maintain the operation of PC 104 circuit cards in environments that include elevated temperatures.